This invention pertains to tube fin trimming machines for elongated tube fins, and pertains particularly to a tube fin trimming machine and method for accurately trimming elongated tubular structures longitudinally so as to provide precisely tapered shapes for the fins.
It is known for components of boilers and the like to have water-cooled or steam-cooled walls made of boiler tubing, to which metal flatstock material has been welded onto a tube longitudinally so as to form an elongated fin on opposite sides of the tube. When constructing certain boiler components, such as furnaces or cyclones having circular cross-sections that continuously vary in diameter, portions of the component may require that the tubes themselves be arranged locally in a converging or diverging pattern. Such constructions require that the tube fin be tapered.
Welding of fins or spacers between adjacent elongated tubes for boiler construction is disclosed by U.S. Pat. No. 3,258,577 to Smith, in which welding apparatus is moved longitudinally relative to the tube. U.S. Pat. No. 4,003,556 to Roeder and U.S. Pat. No. 4,180,248 to Benko disclose flame cutting machines utilizing a moving torch carriage configuration. U.S. Pat. No. 4,471,948 to Holmes discloses apparatus for torch cutting elongated members such as rails. U.S. Pat. No. 4,747,886 to Dankovic et al discloses a device for torch cutting fins from elongated tubes. Also, U.S. Pat. No. 4,798,321 to Moran discloses a panelizing machine used for welding together adjacent finned tubes by longitudinal movement of the welding apparatus relative to the tubes, so as to form wall panels useful in steam boiler construction. However, the known prior art has apparently not provided a device suitable for performing accurate longitudinal trimming of such finned tubes in a rapid and efficient manner.